Remove the need to specify the pbr hook

If you're running pbr codepaths, you want the hook. There is no need
to say "pbr=True" in setup.py and then to list the hook in setup.cfg
now that d2to1 is in the tree.

Change-Id: Ie33d3e08d5a4133f5caf2613859919ce4f02c4a0

README.rst

@@ -124,9 +124,6 @@ A simple sample can be found in pbr s own setup.cfg
  [files]
  packages =
      oslo
- [hooks]
- setup-hooks =
-     pbr.hooks.setup_hook
 
 The minimal setup.py should look something like this::
 

pbr/tests/__init__.py

@@ -79,6 +79,7 @@ class BaseTestCase(testtools.TestCase, testresources.ResourcedTestCase):
 
         self.useFixture(fixtures.NestedTempfile())
         self.useFixture(fixtures.FakeLogger())
+        self.useFixture(fixtures.EnvironmentVariable('PBR_VERSION', '0.0'))
 
         self.temp_dir = self.useFixture(fixtures.TempDir()).path
         self.package_dir = os.path.join(self.temp_dir, 'testpackage')

pbr/util.py

@@ -77,6 +77,7 @@ try:
 except ImportError:
     import ConfigParser as configparser
 
+import pbr.hooks
 
 # A simplified RE for this; just checks that the line ends with version
 # predicates in ()
@@ -219,7 +220,9 @@ def cfg_to_args(path='setup.cfg'):
 
     try:
         if setup_hooks:
-            setup_hooks = split_multiline(setup_hooks)
+            setup_hooks = [
+                hook for hook in split_multiline(setup_hooks)
+                if hook != 'pbr.hook.setup_hook']
             for hook in setup_hooks:
                 hook_fn = resolve_name(hook)
                 try :
@@ -233,6 +236,9 @@ def cfg_to_args(path='setup.cfg'):
                     log.error(traceback.format_exc())
                     sys.exit(1)
 
+        # Run the pbr hook
+        pbr.hooks.setup_hook(config)
+
         kwargs = setup_cfg_to_setup_kwargs(config)
 
         # Set default config overrides